Process of producing composition of matter



Lia

ama- Sept. 27, rear 1 are WILLSON H. ROWLEY, OF CHAELESTON, WEST VIRGINIA, ASSIGNOR TO EVANS LEAD COMPANY, OF CKARLESTON, WEST VIRGINIA, A CORPORATION OF DELAWARE PROCESS OF PRODUCING COMPOSITION OF MATTER No Drawing.

In storage batteries, particularly automobile starting and lighting batteries, much depends upon the negative plates for best capacities. In such batteries there is a tendency of the sponge lead composing the active material of the negative plate to contract, coagulate and weld together the lead particles. As this contraction, coagulation and welding together is more noticeable in cold weather, the capacity of the plates is greatly reduced and sometimes the battery is thereby rendered worthless.

With these facts in mind the present invention is directed to a new material to be used in the making of negative plates of the pasted variety for storage batteries or storage cells, and has for one of its objects the provision of a material which not only promotes separation of the lead particles of the plate mass but maintains this particle separation thereby or mix used in making negative plates. This dry material is not only non-corrosive, but it is easily mixed with battery oxides to give a .uniform paste with a minimum of effort.

Moreover, by means of this dry material the proportions of the dry material and battery oxides can be more easily adhered to by a workman unskilled in the art of battery mak ing, thereby duction. The dry materialalso has good eeping qualities, and it can be stored or shipped without deterioration.

More specifically the present invention is directed to the production of a new composition of matter for use .in the manufacture of negative plates and storage batteries, this new giving uniform results in pro-- Application filed'November 7, 1930. Serial No. 494,194.

composition of matter resulting from the mixing of a material, such as lead oxide for example, capable of combining chemically with the acids in the mass which'results from treating a fibrous cellulosic carbon-containing material with sulphuric acid.

By way of example I may take 14 ounces of sulphuric acid of a specific gravity of 1.400- or thereabouts, heat the same to about 225 F., then add 50 grams of a suitable fibrous cellulosic carbon-containing material, such as hemp for example, to the acid, and after the cellulosic material has become thoroughly in corporated with the acid I maintain the heat for a suitable period of time (say from five to ten minutes) until the cellulosic material has become partially carbonized but still retaining afibrous condition.

The treatment of hemp or other suitabl fibrous cellulosic material with sulphuric duction products of the sulphuric acid, partial decomposition products of oxycellulose,

and also soluble organic salts, such as sulphonates and sulphates of sugars, which latter are capable of forming lead salts on treatment with lead oxides.

The heating is then discontinued and the resulting mass, preferably when cooled, is mixed with lead oxide in such proportions that all of the liquid of the mass will combine with the oxide. I have found that about 2,500 cubic centimeters of the material to 17% pounds of lead oxide (PbO) will be about the right proportions with the result that the lead oxide not only combines with the unreacted sulphuric acid and the unreacted reduction products but also with the sulphonates of the organic matter carried in the sulphuric acid to form lead sulphonates may be dried and reduced by a. suitable mill to a powder, and in this condition incorporated in the paste or mix wed in making negative plates.

I have found that the addition of my improved material to the plate mix results in increased sulphation of the lead oxide and an increase in bulking, the latterfeature pervknown commercially as expanders, in that excessive swelling of the plate is eliminated. This is of advantage because it avoids entirely the danger. of the plates swelling to such a degree as to contact with the positive plates and thus cause a short circuit in the battery. It also. eliminates sloughing of the active mass from-the supporting grid. It further eliminates entirely the difiiculty experienced with prior plates when removing the same from the cell and placing them again in position.

While I have referred to lead oxide as a material suitable for carrying out my invention, it is tobe understood, however, that other materials such for example as basic lead sulphate or metallic lead powder may be used with good results. I

This application is a continuation in part of my application Serial No. 348,973, filed March 21, 1929. A

What I claim is I 1. In the manufacture of a material for addition to the negative plate mix for storage batteries, the process which comprises heating a mixture of cellulosic fibrous material and sulphuric acid until the said material is a partially-carbonized fibrous material,

discontinuing said heating, mixing the resulting mass with lead oxide in such amounts 1 that substantially all of the acid of the mass will combine with theoxide, drying, and reducing to a powder.

2. In the manufacture of a material for addition to the negative. plate mix for storage batteries, the process which comprises heating a mixture of hemp and sulphuric acid until the hemp is a partially-carbonized fibrous material, discontinuing said heating, mixing the resulting mass with lead oxide, drying, and reducing to a powder.

rial and sulphuric acid at about 225 F. until the said material is a partially-carbonized fibrous material, discontinuing said heating, then cooling, mixing the cooled mass with lead oxide until the acid of the mass is substantially all combined, drying and powderi. In the manufacture of a material for addition to the negative plate mix for storage batteries, the process which comprises heating a mixture of fibrous, cellulosic material and sulphuric acid having a specific gravity of about 1.400 at a temperature of about 225 F. in the proportions of approximately 50 grams of the material to 14 ounces of the acid until the said material is a. partially-carbonized fibrous material, discontinuing said heating then cooling, and mix ing the resulting mass with lead oxide approximately in theproportions of 2,500 cubic centimeters of the mass to 17 pounds of the oxide, drying, and reducing to a powder.

5. In the manufacture of a material for addition to negative plate material for storage batteries, the process which comprises heating a fibrous cellulosic material and sulphuric acid until the said material is a partially-carbonized fibrous material, discontinuing said heating, and mixing the result-, ing mass with lead oxide in suflicient quantity to combine with substantially all the free sulphuric acid of the mass.

6. In the manufacture of a material to be added to a negative plate mix for storage batteries, the process which comprises heating hemp and sulphuric acid until the hemp is a partially-carbonized fibrous material, discontinuing said heating, and mixing the resulting mass with lead oxide in suflicient I quantity to combine with substantially allof the free sulphuric acid of the mass.

This specification signed this 5th day of November, 1930. t

- WHJLSON H. ROWLEY.

3. In the manufacture of a material for addition to the negative plate mix for storage batteries, the process which comprises heating a mixture of fibrous, cellulosic mate 

